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authorLinus Torvalds <torvalds@linux-foundation.org>2018-05-25 09:35:11 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2018-05-25 09:35:11 -0700
commit62d18ecfa64137349fac9c5817784fbd48b54f48 (patch)
tree0679451428581ecd92abf04b9e0a66c812d0d58c /arch
parentb133ef6ea4c918bb70f40e6c522f1a474eecd589 (diff)
parent82034c23fcbc2389c73d97737f61fa2dd6526413 (diff)
Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull more arm64 fixes from Will Deacon: - fix application of read-only permissions to kernel section mappings - sanitise reported ESR values for signals delivered on a kernel address - ensure tishift GCC helpers are exported to modules - fix inline asm constraints for some LSE atomics * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: Make sure permission updates happen for pmd/pud arm64: fault: Don't leak data in ESR context for user fault on kernel VA arm64: export tishift functions to modules arm64: lse: Add early clobbers to some input/output asm operands
Diffstat (limited to 'arch')
-rw-r--r--arch/arm64/include/asm/atomic_lse.h24
-rw-r--r--arch/arm64/kernel/arm64ksyms.c8
-rw-r--r--arch/arm64/lib/tishift.S15
-rw-r--r--arch/arm64/mm/fault.c51
-rw-r--r--arch/arm64/mm/mmu.c16
5 files changed, 83 insertions, 31 deletions
diff --git a/arch/arm64/include/asm/atomic_lse.h b/arch/arm64/include/asm/atomic_lse.h
index 9ef0797380cb..f9b0b09153e0 100644
--- a/arch/arm64/include/asm/atomic_lse.h
+++ b/arch/arm64/include/asm/atomic_lse.h
@@ -117,7 +117,7 @@ static inline void atomic_and(int i, atomic_t *v)
/* LSE atomics */
" mvn %w[i], %w[i]\n"
" stclr %w[i], %[v]")
- : [i] "+r" (w0), [v] "+Q" (v->counter)
+ : [i] "+&r" (w0), [v] "+Q" (v->counter)
: "r" (x1)
: __LL_SC_CLOBBERS);
}
@@ -135,7 +135,7 @@ static inline int atomic_fetch_and##name(int i, atomic_t *v) \
/* LSE atomics */ \
" mvn %w[i], %w[i]\n" \
" ldclr" #mb " %w[i], %w[i], %[v]") \
- : [i] "+r" (w0), [v] "+Q" (v->counter) \
+ : [i] "+&r" (w0), [v] "+Q" (v->counter) \
: "r" (x1) \
: __LL_SC_CLOBBERS, ##cl); \
\
@@ -161,7 +161,7 @@ static inline void atomic_sub(int i, atomic_t *v)
/* LSE atomics */
" neg %w[i], %w[i]\n"
" stadd %w[i], %[v]")
- : [i] "+r" (w0), [v] "+Q" (v->counter)
+ : [i] "+&r" (w0), [v] "+Q" (v->counter)
: "r" (x1)
: __LL_SC_CLOBBERS);
}
@@ -180,7 +180,7 @@ static inline int atomic_sub_return##name(int i, atomic_t *v) \
" neg %w[i], %w[i]\n" \
" ldadd" #mb " %w[i], w30, %[v]\n" \
" add %w[i], %w[i], w30") \
- : [i] "+r" (w0), [v] "+Q" (v->counter) \
+ : [i] "+&r" (w0), [v] "+Q" (v->counter) \
: "r" (x1) \
: __LL_SC_CLOBBERS , ##cl); \
\
@@ -207,7 +207,7 @@ static inline int atomic_fetch_sub##name(int i, atomic_t *v) \
/* LSE atomics */ \
" neg %w[i], %w[i]\n" \
" ldadd" #mb " %w[i], %w[i], %[v]") \
- : [i] "+r" (w0), [v] "+Q" (v->counter) \
+ : [i] "+&r" (w0), [v] "+Q" (v->counter) \
: "r" (x1) \
: __LL_SC_CLOBBERS, ##cl); \
\
@@ -314,7 +314,7 @@ static inline void atomic64_and(long i, atomic64_t *v)
/* LSE atomics */
" mvn %[i], %[i]\n"
" stclr %[i], %[v]")
- : [i] "+r" (x0), [v] "+Q" (v->counter)
+ : [i] "+&r" (x0), [v] "+Q" (v->counter)
: "r" (x1)
: __LL_SC_CLOBBERS);
}
@@ -332,7 +332,7 @@ static inline long atomic64_fetch_and##name(long i, atomic64_t *v) \
/* LSE atomics */ \
" mvn %[i], %[i]\n" \
" ldclr" #mb " %[i], %[i], %[v]") \
- : [i] "+r" (x0), [v] "+Q" (v->counter) \
+ : [i] "+&r" (x0), [v] "+Q" (v->counter) \
: "r" (x1) \
: __LL_SC_CLOBBERS, ##cl); \
\
@@ -358,7 +358,7 @@ static inline void atomic64_sub(long i, atomic64_t *v)
/* LSE atomics */
" neg %[i], %[i]\n"
" stadd %[i], %[v]")
- : [i] "+r" (x0), [v] "+Q" (v->counter)
+ : [i] "+&r" (x0), [v] "+Q" (v->counter)
: "r" (x1)
: __LL_SC_CLOBBERS);
}
@@ -377,7 +377,7 @@ static inline long atomic64_sub_return##name(long i, atomic64_t *v) \
" neg %[i], %[i]\n" \
" ldadd" #mb " %[i], x30, %[v]\n" \
" add %[i], %[i], x30") \
- : [i] "+r" (x0), [v] "+Q" (v->counter) \
+ : [i] "+&r" (x0), [v] "+Q" (v->counter) \
: "r" (x1) \
: __LL_SC_CLOBBERS, ##cl); \
\
@@ -404,7 +404,7 @@ static inline long atomic64_fetch_sub##name(long i, atomic64_t *v) \
/* LSE atomics */ \
" neg %[i], %[i]\n" \
" ldadd" #mb " %[i], %[i], %[v]") \
- : [i] "+r" (x0), [v] "+Q" (v->counter) \
+ : [i] "+&r" (x0), [v] "+Q" (v->counter) \
: "r" (x1) \
: __LL_SC_CLOBBERS, ##cl); \
\
@@ -435,7 +435,7 @@ static inline long atomic64_dec_if_positive(atomic64_t *v)
" sub x30, x30, %[ret]\n"
" cbnz x30, 1b\n"
"2:")
- : [ret] "+r" (x0), [v] "+Q" (v->counter)
+ : [ret] "+&r" (x0), [v] "+Q" (v->counter)
:
: __LL_SC_CLOBBERS, "cc", "memory");
@@ -516,7 +516,7 @@ static inline long __cmpxchg_double##name(unsigned long old1, \
" eor %[old1], %[old1], %[oldval1]\n" \
" eor %[old2], %[old2], %[oldval2]\n" \
" orr %[old1], %[old1], %[old2]") \
- : [old1] "+r" (x0), [old2] "+r" (x1), \
+ : [old1] "+&r" (x0), [old2] "+&r" (x1), \
[v] "+Q" (*(unsigned long *)ptr) \
: [new1] "r" (x2), [new2] "r" (x3), [ptr] "r" (x4), \
[oldval1] "r" (oldval1), [oldval2] "r" (oldval2) \
diff --git a/arch/arm64/kernel/arm64ksyms.c b/arch/arm64/kernel/arm64ksyms.c
index 66be504edb6c..d894a20b70b2 100644
--- a/arch/arm64/kernel/arm64ksyms.c
+++ b/arch/arm64/kernel/arm64ksyms.c
@@ -75,3 +75,11 @@ NOKPROBE_SYMBOL(_mcount);
/* arm-smccc */
EXPORT_SYMBOL(__arm_smccc_smc);
EXPORT_SYMBOL(__arm_smccc_hvc);
+
+ /* tishift.S */
+extern long long __ashlti3(long long a, int b);
+EXPORT_SYMBOL(__ashlti3);
+extern long long __ashrti3(long long a, int b);
+EXPORT_SYMBOL(__ashrti3);
+extern long long __lshrti3(long long a, int b);
+EXPORT_SYMBOL(__lshrti3);
diff --git a/arch/arm64/lib/tishift.S b/arch/arm64/lib/tishift.S
index d3db9b2cd479..0fdff97794de 100644
--- a/arch/arm64/lib/tishift.S
+++ b/arch/arm64/lib/tishift.S
@@ -1,17 +1,6 @@
-/*
- * Copyright (C) 2017 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+/* SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ * Copyright (C) 2017-2018 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
*/
#include <linux/linkage.h>
diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 4165485e8b6e..2af3dd89bcdb 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -293,6 +293,57 @@ static void __do_kernel_fault(unsigned long addr, unsigned int esr,
static void __do_user_fault(struct siginfo *info, unsigned int esr)
{
current->thread.fault_address = (unsigned long)info->si_addr;
+
+ /*
+ * If the faulting address is in the kernel, we must sanitize the ESR.
+ * From userspace's point of view, kernel-only mappings don't exist
+ * at all, so we report them as level 0 translation faults.
+ * (This is not quite the way that "no mapping there at all" behaves:
+ * an alignment fault not caused by the memory type would take
+ * precedence over translation fault for a real access to empty
+ * space. Unfortunately we can't easily distinguish "alignment fault
+ * not caused by memory type" from "alignment fault caused by memory
+ * type", so we ignore this wrinkle and just return the translation
+ * fault.)
+ */
+ if (current->thread.fault_address >= TASK_SIZE) {
+ switch (ESR_ELx_EC(esr)) {
+ case ESR_ELx_EC_DABT_LOW:
+ /*
+ * These bits provide only information about the
+ * faulting instruction, which userspace knows already.
+ * We explicitly clear bits which are architecturally
+ * RES0 in case they are given meanings in future.
+ * We always report the ESR as if the fault was taken
+ * to EL1 and so ISV and the bits in ISS[23:14] are
+ * clear. (In fact it always will be a fault to EL1.)
+ */
+ esr &= ESR_ELx_EC_MASK | ESR_ELx_IL |
+ ESR_ELx_CM | ESR_ELx_WNR;
+ esr |= ESR_ELx_FSC_FAULT;
+ break;
+ case ESR_ELx_EC_IABT_LOW:
+ /*
+ * Claim a level 0 translation fault.
+ * All other bits are architecturally RES0 for faults
+ * reported with that DFSC value, so we clear them.
+ */
+ esr &= ESR_ELx_EC_MASK | ESR_ELx_IL;
+ esr |= ESR_ELx_FSC_FAULT;
+ break;
+ default:
+ /*
+ * This should never happen (entry.S only brings us
+ * into this code for insn and data aborts from a lower
+ * exception level). Fail safe by not providing an ESR
+ * context record at all.
+ */
+ WARN(1, "ESR 0x%x is not DABT or IABT from EL0\n", esr);
+ esr = 0;
+ break;
+ }
+ }
+
current->thread.fault_code = esr;
arm64_force_sig_info(info, esr_to_fault_info(esr)->name, current);
}
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index 2dbb2c9f1ec1..493ff75670ff 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -933,13 +933,15 @@ int pud_set_huge(pud_t *pudp, phys_addr_t phys, pgprot_t prot)
{
pgprot_t sect_prot = __pgprot(PUD_TYPE_SECT |
pgprot_val(mk_sect_prot(prot)));
+ pud_t new_pud = pfn_pud(__phys_to_pfn(phys), sect_prot);
- /* ioremap_page_range doesn't honour BBM */
- if (pud_present(READ_ONCE(*pudp)))
+ /* Only allow permission changes for now */
+ if (!pgattr_change_is_safe(READ_ONCE(pud_val(*pudp)),
+ pud_val(new_pud)))
return 0;
BUG_ON(phys & ~PUD_MASK);
- set_pud(pudp, pfn_pud(__phys_to_pfn(phys), sect_prot));
+ set_pud(pudp, new_pud);
return 1;
}
@@ -947,13 +949,15 @@ int pmd_set_huge(pmd_t *pmdp, phys_addr_t phys, pgprot_t prot)
{
pgprot_t sect_prot = __pgprot(PMD_TYPE_SECT |
pgprot_val(mk_sect_prot(prot)));
+ pmd_t new_pmd = pfn_pmd(__phys_to_pfn(phys), sect_prot);
- /* ioremap_page_range doesn't honour BBM */
- if (pmd_present(READ_ONCE(*pmdp)))
+ /* Only allow permission changes for now */
+ if (!pgattr_change_is_safe(READ_ONCE(pmd_val(*pmdp)),
+ pmd_val(new_pmd)))
return 0;
BUG_ON(phys & ~PMD_MASK);
- set_pmd(pmdp, pfn_pmd(__phys_to_pfn(phys), sect_prot));
+ set_pmd(pmdp, new_pmd);
return 1;
}